The work aims to improve the electrical conductivity of direct-writing patterns of organic polymer conductive ink. Silver nanoparticles (AgNPs) were added to the poly (3,4-ethylenedioxythiophene): polystyrene sulfonate conductive ink to prepare the composite conductive ink and used to prepare the direct-writing conductive patterns. The resistivity test results of direct-writing patterns indicated that, when the mass fraction of AgNPs was improved from 0 to 10%, the pattern resistivity was reduced from 8.7×107 μΩ∙cm to 931.7 μΩ∙cm. After the 20 MPa pressure treatment for 10 min, the pattern resistivity was further reduced. When the mass fraction of AgNPs was 0 and 10%, the pattern resistivity was respectively reduced to 4.2×107 and 93.8 μΩ∙cm. When the mass fraction of AgNPs was more than 10%, nanoparticles would be subject to severe agglomeration. The particles and polymer were not uniformly mixed, thus resulting in non-uniform pattern resistance. As the voids in the microstructure were increased, the pattern resistivity was increased. Addition of a proper amount of silver nanoparticles to the conductive polymer is a feasible way to improve the electrical conductivity of its direct-writing patterns. There is no limitation in substrate material selection because such direct-writing patterns require no high temperature sintering. The mechanism of the electrical conductivity improvement of direct-writing patterns by the silver nanoparticles is that more paths are provided for the electrons. The PP/AgNPs composite ink is expected to be used for printing the antenna of RFID (Radio Frequency Identification) tag.